# CVE-2015-5470: Denial of service in n/a

> Remote attackers can cause denial of service via CPU consumption or crash in PowerDNS Recursor and Authoritative Server through crafted DNS requests.

- **Severity:** High 7.8 (`AV:N/AC:L/Au:N/C:N/I:N/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Nov 2015
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2015-5470, DSA-3306-1, DSA-3307-1, GHSA-vh8j-jj36-28wq, UBUNTU-CVE-2015-5470

## What is CVE-2015-5470?

CVE-2015-5470 is a high-severity denial of service vulnerability in Powerdns Recursor, published on 2 Nov 2015. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The label decompression functionality in PowerDNS Recursor before 3.6.4 and 3.7.x before 3.7.3 and Authoritative (Auth) Server before 3.3.3 and 3.4.x before 3.4.5 allows remote attackers to cause a denial of service (CPU consumption or crash) via a request with a long name that refers to itself.  NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-1868.

Weakness: CWE-399

## Which versions are affected by CVE-2015-5470?

It affects 2 products.


Products: Powerdns Authoritative, Powerdns Recursor.

## How do I fix CVE-2015-5470?

Upgrade to a fixed version.

## Is CVE-2015-5470 being exploited?

There is no known exploitation of CVE-2015-5470 in the wild and no public exploit code.

## Other vulnerabilities in Powerdns Recursor

- [CVE-2020-24698](https://insights.sbomify.com/CVE-2020-24698/): Use after free in n/a (critical 9.8)
- [CVE-2020-24696](https://insights.sbomify.com/CVE-2020-24696/): Race condition in n/a (high 8.1)
- [CVE-2026-42001](https://insights.sbomify.com/CVE-2026-42001/): Insufficient Validation of Autoprimary SOA Queries (high 7.5)
- [CVE-2020-24697](https://insights.sbomify.com/CVE-2020-24697/): Denial of service in n/a (high 7.5)
- [CVE-2016-5426](https://insights.sbomify.com/CVE-2016-5426/): Denial of service in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2015-5470 and fix it if it is affected.

What it is: CVE-2015-5470 is a high-severity denial of service vulnerability in Powerdns Recursor, published on 2 Nov 2015. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2015-5470 in the wild and no public exploit code.

Affected product: Powerdns Recursor. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2015-5470/ (Markdown: https://insights.sbomify.com/CVE-2015-5470/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2015-5470
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2015-5470
- OSV: https://osv.dev/vulnerability/CVE-2015-5470

---
From sbomify Insights: https://insights.sbomify.com/CVE-2015-5470/
Summaries are generated and may contain mistakes; the official description above is the record.